In conventional radio communication apparatuses, as a configuration capable of supporting a plurality of radio communication schemes with a single apparatus, there is a configuration in which wireless sections capable of performing communication respectively in the plurality of communication schemes are provided, and the used wireless sections are switched as necessary (See Patent Document 1). FIG. 1 shows the same configuration as in the conventional radio communication apparatus disclosed in Patent Document 1.
In FIG. 1, scheme 1 compatible wireless section 902 is connected to antenna 901 supporting a first communication scheme and performs predetermined radio signal processing supporting the first communication scheme. Scheme 2 compatible wireless section 904 is connected to antenna 903 supporting a second communication scheme and performs predetermined radio signal processing supporting the second communication scheme. Upper layer processing section 905 is, for example, configured with a CPU (central processing unit) that determines which of the first communication scheme and the second communication scheme is selected to perform communication, and executes processing at the upper layer in each communication. That is, in the radio communication apparatus shown in FIG. 1, modules supporting the plurality of communication schemes are provided respectively, and one of the schemes is selected to perform communication as necessary.
Also, there are apparatuses adopting a configuration capable of supporting the plurality of the communication schemes with a single radio apparatus, what is called, software radio equipment (See Patent Document 2). FIG. 2 shows a configuration that is the same as a digital signal processing section of the radio communication apparatus configured with the conventional software radio equipment that is disclosed in Patent Document 2.
In the apparatus configuration shown in FIG. 2, digital signal processing section 910 executes so-called A/D conversion processing in which analog/digital conversion section 911 receives analog received signals such as RF signals, IF signals and baseband signals from the wireless section upon reception, performs quantization, converts these signals to digital signals, and outputs the digital signals. The obtained digital signals are stored temporarily in I/O buffer 912 as necessary, and readout and supplied to bus 913 as necessary. The supplied digital signals are subjected to digital signal processing for reception based on a predetermined program in FPGA (Field Programmable Gate Array) section 914 and DSP (Digital Signal Processor) section 915, and the obtained reception data sequences are supplied to a block (e.g., a CPU section) etc. that performs application processing.
Upon transmission, the transmission data supplied via bus 913 from the application processing section are subjected to digital signal processing for transmission based on the predetermined program in FPGA section 914 and DSP section 915. Thus, the obtained transmission signals are temporarily stored in I/O buffer 912 as necessary, read out as necessary, converted to analog signals such as baseband signals, IF signals and RF signals for transmission in analog/digital conversion section 911, and supplied to the wireless section. In Patent Document 2, the software radio equipment is configured by connecting digital signal processing section 910 and the wireless section.
The predetermined programs that are executed in FPGA section 914 and DSP section 915 may be, for example, a software program for DSP or a program describing the circuit configuration in the FPGA. These programs are stored in a re-writable memory and can be read out upon start up of the apparatus or as necessary. Digital signal processing section 910 can support different communication schemes by reading-in and executing different programs as necessary in FPGA section 914 and DSP section 915.    Patent Document 1: Japanese Patent Application Laid-open No. 2000-216698 (Page 6, FIG. 1)    Patent Document 2: Japanese Patent Application Laid-open No. 2001-189675 (Page 7, FIG. 1)